Now working.
My Savfy A4 LED lightbox (model A4-DWT) stopped turning on after about 2yrs. I pealed off the back which was held on with double sided adhesive tape to expose the tiny circuit board with its string of 21 LED’s. All looked fine and there was 5v on the circuit board from the USB supply, as expected.
The board had a capacitive disc for switching, unmarked IC, A09T transistor, a few capacitors and resistors. All to turn of/on and do dimming/brightening.
I found just touching the front or the rear of the circuit board, by the capacitive disc, with my finger (its only 5v so quite safe) showed every working.
So I drilled and chamfered a 10mm hole in the 0,5mm thick plastic rear cover (and covered with sellotape to keep out dus) so I had finger access to the capacitive disc area and everything worked.
(I suppose I could have removed and drilled the hole in the front cover which would have been more touch sensitive (as the disc is on the top surface of the circuit board) but it looked better having the hole on the under surface where it couldn’t be seen).
I don’t know why the capacitive switching assembly became less sensitive and needed
this modification, perhaps the IC or transistor was degrading with time/usage.
Images show front of circuit board and drilled hole
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12 Commenti
I have this problem to, but I think its something with the wires, Its super sensitive and randomly shuts off while im tracing, Im not sure if I should get a new cord or maybe its something internal?
da Tootsie
Im having this problem also and it is brand new! i cant find help anywhere !
da ricky.carralero
Hi I've got the same problem. The switch seems to be broken but I can't figure out how to open the lightpad in order to change the switch.
da Peter Brouwers
Yes mines just gone, the lead is loose and a poor fit. Last night it flickered and went off not worked since despite buying a new lead. The fixture inside the box that connect the lead is the problem, it’s too wide for the connector to fit snug. Mines going in the bin and see if I can buy a better one.
da ydewale
Pull the white back off it’s only taped on.
da ydewale
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